SLLSFZ7 February 2025 TUSB1146-Q1
PRODUCTION DATA
In Fixed EQ operation, a single EQ setting is used for all possible devices inserted into the USB-C receptacle (with or without USB cable). TI recommends to set the TUSB1146-Q1 EQ[1:0] pins if GPIO mode, or EQ1_SEL and EQ2_SEL if I2C mode to approximately 4db to 5dB greater than loss of the post channel (MIN(XEF, XGH)). For example, if post channel is 0.5 inches, then assuming –1dB per inch at 5GHz, program the EQ1_SEL and EQ2_SEL between 4.5dB to 5.5dB. TI recommends performing USB3.1 Rx JTOL long and short channel tests to optimize the setting. Depending on the USB 3.1 Host, a single EQ setting which satisfies both the long and short channel tests may not be possible. If this is the case, then TI recommends to use Fast or Full AEQ mode.